Ring-Closing Metathesis on Solid Support: Elaboration of a Cyclization/Cleavage Strategy Towards Unsaturated α-Ester-Substituted N-Heterocycles

A Ru-mediated strategy for the cleavage of organic substrate molecules from a solid support via ring-closing metathesis is described. Application of this protocol to solid phase-bound olefinic amino acid derivatives provides various highly functionalized unsaturated N-heterocycles of different ring-sizes in moderate to excellent yields. This strategy features the addition of a stoichiometric amount of styrene to the metathesis mixture, which is shown to increase the yield of the reaction.